1. Field of the Invention
The present invention relates to an electric rotating machine for starter motor and a manufacturing method of the same. More particularly, the present invention relates to a stator structure and its manufacturing method.
2. Related Art
It is known, by Japanese Laid-open Patent No. 61-10950, to manufacture a stator of an electric rotating machine by a method of fixing permanent magnets as magnetic poles onto a yoke by rounding an elastic copper band to a cylindrical body and butting it in the circumferential end and pressing it in, to fix the permanent magnets onto the inner circumference of the yoke.
With the conventional structure and method, the circumferential end portion of the cylindrical body is butted and projected between the space between the permanent magnets. The inner diameter of the magnetic poles fluctuates according to the magnet thickness and dimensional error of the inner diameter of the yoke, so the tension force of the butt portion may be insufficient, the pressing force of the magnet onto the yoke by the cylindrical body may drop, and the stress of the portion projected between the permanent magnets may become excessive.